摘要：
Christmas is coming and everyone is building a Christmas tree, and you are no exception. However you are special and you want to build a special one. 阅读全文
摘要：
A sequence of positive rational numbers is defined as follows:An infinite full binary tree labeled by positive rational numbers is defined by: The la 阅读全文
摘要：
对正整数n，欧拉函数是少于或等于n的数中与n互质的数的数目。例如euler(8)=4，因为1,3,5,7均和8互质。 Euler函数表达通式：euler(x)=x(1-1/p1)(1-1/p2)(1-1/p3)(1-1/p4)…(1-1/pn),其中p1,p2……pn为x的所有素因数，x是不为0的整 阅读全文